The pilots, aircrew and passengers of today's military and commercial aircraft are faced with a substantial threat of head and cervical spine injuries. For example, the recent addition of strengthened airframes, ruggedized fuel cells, energy absorbant landing gear and load limiting seats in the various helicopters have made approximately 80% of crashes potentially survivable, according to published data. The primary remaining hazard is cockpit strikes. Insufficient cockpit room for crew displacement, protruding controls and cockpit panels are the current threat to aircrew. Sixty-five percent of 153 projected deaths in a specific helicopter program will be from cockpit strikes, resulting in medical expenses and crew replacement costs in excess of $21 million. Even a properly maintained and adjusted restraint system experiences slack and elongation--the cause of cockpit injuries.
In the case of serious injury, broken jaws, etc., a crew member might be rendered unconscious, thereby unable to depart from the wrecked vehicle. Additionally, flailing of the head in a crash situation often causes debilitation head and cervical injury.